Debian Long Term Support / LTS Security Information / 2019 / Security Information -- DLA-1762-1 systemd

Debian Security Advisory

DLA-1762-1 systemd -- LTS security update

Date Reported:

24 Apr 2019

Affected Packages:

systemd

Vulnerable:

Yes

Security database references:

In Mitre's CVE dictionary: CVE-2017-18078, CVE-2019-3842.

More information:

Two vulnerabilities have been addressed in the systemd components systemd-tmpfiles and pam_systemd.so.

• CVE-2017-18078

  systemd-tmpfiles in systemd attempted to support ownership/permission changes on hardlinked files even if the fs.protected_hardlinks sysctl is turned off, which allowed local users to bypass intended access restrictions via vectors involving a hard link to a file for which the user lacked write access.

• CVE-2019-3842

  It was discovered that pam_systemd did not properly sanitize the environment before using the XDG_SEAT variable. It was possible for an attacker, in some particular configurations, to set a XDG_SEAT environment variable which allowed for commands to be checked against polkit policies using the allow_active element rather than allow_any.

For Debian 8 Jessie, these problems have been fixed in version 215-17+deb8u12.

We recommend that you upgrade your systemd packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS